It is commonly asked whether language is learned or innate. This proposal recasts the question so that it is amenable to investigation, asking which aspects of language development are more (or less) sensitive to linguistic and environmental input. The proposal describes a research plan to identify the properties of language whose development can withstand wide variations in learning conditions -- the "resilient" properties of language. Children who have not been exposed to conventional linguistic input will be observed in order to determine which properties of language can be developed under one set of severely degraded input conditions. The subjects of the study are deaf children with hearing losses so extensive that they cannot naturally acquire oral language, and born to hearing parents who have not yet exposed them to a manual language. Under such inopportune conditions, one might expect no symbolic communication at all or, at the least, communication which is unlike conventional language. This turns out not to be the case. Previous research has shown that, despite these impoverished language-learning conditions, American deaf children were able to develop gestural communication systems which were structured as are the early communication systems of children acquiring language from conventional language models. The proposed research will determine whether deaf children lacking conventional language models in another culture (a Chinese culture) can develop gesture systems that are similarly structured, i.e., the project will determine the resilience of various properties of language in the face of wide cultural variation. Study 1 will explore how hearing mothers of deaf children between the ages of 3 and 5 interact with their children in Taiwan and in America, and thus will attempt to verify the assumption that mothers interact quite differently with their children in Chinese and American cultures. Study 2 will explore the spontaneous gestures that Chinese and American mothers produce when interacting with their deaf children. In so doing, the study will determine the type of gestural model that the deaf child in each culture receives as input. If the mothers in the two cultures do provide their deaf children with different gestural models, it becomes particularly important to ask whether the deaf children's gesture systems are more comparable to their mothers' gesture systems or to one another. Thus, Study 3 will analyze the gestures produced by the Chinese deaf children, and compare them to the gestures produced by the American deaf children. It is precisely the properties of language which are found in the gestures of both groups of children (and not in the gestures of the mothers) that can be said to be resilient across cultural variation. Study 4 will attempt to put these studies of gesture in a cultural context by exploring the gestures of four hearing mothers and their hearing children (between the ages of 3 and 4) in each culture, and comparing these observations to the data gathered on the Chinese and American hearing mothers and their deaf children.